<form class="form row-fluid" action="?c=plugin&a=mycss_save" method="post">
<h2 class="main_board"><?=__('PL_CSS_MODIFIER_MENU_TITLE')?></h2> 
<div class="line"></div>
<textarea class="span8" rows="15" id="mycss" name="css" placeholder="body { background: white; }"><?=htmlspecialchars($css)?></textarea>
<p><button type="submit" class="btn"><?=__('UPDATE')?></button></p>
</form>
<script>
tabIndent.render(document.getElementById('mycss'));
</script>